"Charlie Bit My Finger" and "David After Dentist" have a new challenger: "Sadie Doesn't Want Her Brother to Grow Up."

In what has to be one of the cutest-ever meltdowns over the inexorable march of time, 5-year-old Sadie Miller completely loses it over her fear that her 3-month-old brother, Carson, will one day cease to be a baby. "I don't want him to grow up!" she exclaims, hugging Carson's currently baby-sized head. "He's so cute!"

It's not just love for her brother. Sadie also fears for her own future: "And I don't want to die when I'm 100!"

The children's father, Ryan Miller, explained to Time that little Sadie has previously expressed fears about mortality: "She's cried about not wanting to get older herself in the past, but this was the first time she was upset about her brother," he said. "The funny thing is that this was totally out of the blue. We have no idea what prompted it."